Function Decoder Problem

[murphyfp]

With V2.19 loaded into a 16F630 PIC Chip I am unable to READ or WRITE CV's With a Hornby Elite Command Station.
The same problem with a ESU Decoder Programmer and a Dynamis Command Station.

With a Roco Command Station I CAN READ or WRITE CV's

Also the 16F630 PIC chip will not retain the CV's changed on power off.
But if the V2.19 is in a 16F676 PIC chip the changes are retained on power off.

CV change to invert all outputs CV99 changed from Value 0 to 255.

I also need to remap the eight outputs to F1 to F8

One or two problems any ideas anyone please.
Richard

[suzie]

Richard

Reading CVs is dependant on the load that you have on the outputs. Some command stations are able to read with lower load than others. The load should be at least 60mA. If you have a low power output decoder you will need to load up at least three of the outputs to get 60mA, and probably more if you have LEDs connected at normal brightness.

[murphyfp]

Hi Suzie
Thank you for the reply
I have tried loading the DCC rail with 220 Ohm Resistor also I I had a loco on the DCC Rail also with the same result

[suzie]

Neither of those methods will help. You need the load on the output of the decoder. in the case of a low power decoder, you would need 220R resistors on at least three of the outputs.

The first method you describe is a way to resolve problems with some programmers, and the second method just lets you read what is in the loco - you could take the function decoder off the programming track altogether and get the same result!

[Paul Harman]

Not sure why you are seeing the loss of CVs in the 16F630. I must admit that most of my testing is done with 16F676 because I got a lot of them cheap, but I have tried a 16F630 and it was fine. Some of the older versions of firmware result in CV loss when reading CVs using direct mode, but that should be fixed in v2.19.